Management of Lake Nockamixon Habitats by Gina Frederick

Expansion of the existing riparian buffer in ZONE A is a BMP which will slow, reduce, clean, and infiltrate stormwater from the extensive impervious, upslope parking area. In addition to intercepting stormwater, expansion of the existing riparian buffer will increase wildlife value, as an increase in native plants will supply many birds and insects with food sources and shelter.

Before planting the riparian buffer, an invasive plant management plan should be implemented to eradicate the most pernicious weeds. Suggested target species for elimination include Japanese Honeysuckle, Multiflora Rose, Loosestrife, and Autumn Olive. Techniques for removing these plants are listed on page 31.

If a completely unobstructed view of the lake along ZONE A is desired, planting trees may not be possible in this area. However, maintaining this area as low shrubbery will be more time consuming and expensive, requiring continual removal of volunteer tree seedlings. If, instead, particular points along the bank are planted with canopy trees which can be limbed up, maintenance requirements will be reduced, the plant community will look and function more naturally, biodiversity will increase, and a view to the lake will endure.

Riparian Buffer Management

Due to deer pressure and environmental factors, a 70% to 80% survival rate of riparian plants should be expected in the first year. After the first year, established plants will begin to colonize and grow more rapidly. Dense coverage of the riparian buffer should occur between the third and fifth year, depending on the level of pressure.

Success of this area can be measured by use of transects and photo documentation. Transects provide a record of plant size and location for distinct areas, while photography allows for an overall comparison of the entire area from year to year.

Native Lowland

The Juniper grove, indicated on the map as ZONE D, consists primarily of Eastern Red Cedar, native evergreen trees with high wildlife value. The lower limbs of these trees are high enough for visibility to the lake.

Invasive plants which once overtook the understory of the Cedar grove have recently been removed. However, pervasive weeds such as Poison Ivy and Autumn Olive will require ongoing removal efforts. Any understory plants selected for this area must be shade tolerant, drought tolerant, and capable of withstanding periodic soil saturation.

These native grasses are well suited for dry to mesic and shaded to sunny sites. Pennsylvania Sedge and Appalachain Sedge are the lowest grasses, reaching 18” and forming low dense turf-like colonies. Because seed for these grasses is not available in the trade, establishment relies on plug planting which is more expensive and labor intensive. The most cost effective method of establishing a low vegetative cover is seed broadcast of a mixture of the other native grasses which reach a height of 3 feet.

The least expensive grass seed alternative is use of multiple native Wild Ryes. These grasses are considered short lived perennials, but they will persist longer in shaded areas.

Native Lowland Management

Successful restoration of the native lowland will depend on careful planning, implementation, and maintenance. In order to eradicate the invasives and establish the native grass ground cover, the following schedule is suggested:

Early Spring: Apply Rodeo® to invasives.

Seed area with a cover crop (annual rye) or cover area with wood chips to prevent erosion. Wood chips should be from trees without alleleopathic properties (Norway Maple, Acer platanoides).